You start off by making the rectangle. I didn't use paper to piece - but feel free if it helps you. Rather than cutting it to the 4.5" x 10.5" I cut mine to 3.5". This extra inch is for the white fabric.
Cut the white fabric into strips - 1" x at least 10.5". After you cut your rectangle to the 3.5" x 10.5", add the 1" white strip to either side.
From this point on the tutorial is pretty much the same, but I'll still walk you through it with my pictures. Cut the 2.25" square and halve it to get your triangle. Attach the triangle to your rule as shown and cut off each corner.
I squared each block to 7.25". I think the hardest part about this block is going to be trying to match up the white lines. So, if you can get yours to line up well, go ahead and piece the 4 blocks into one large block. If you'd rather leave that for me, that's fine too, but then please don't sqare the blocks up - leave that for me. I think it will be easier if I have more fabric to work with when squaring up.
That's it! Let me know if you have any questions!